Microsoft did not invent, research, develop, or make available to the public mobile devices employing the AndroidTM Operating System and other open source operating systems, but nevertheless seeks to dominate something it did not invent. On information and belief, Microsoft intends to take and has taken definite steps towards making competing operating systems such as the AndroidTM Operating System unusable and unattractive to both consumers and device manufacturers through exorbitant license fees and absurd licensing restrictions that bear no relation to the scope and subject matter of its own patents

Ouch indeed, that is a bad reply. The fact that it is open source does not matter for example. If that is the best of what B&N lawyers came up with they are not going to fare to well I think.

The document as a whole is pretty detailed. What's in that one quoted passage is just an allegation of course, but they back it up with specific charges that touch on antitrust matters, knowingly lying to the PTO about certain patents, and a record of Microsoft's conduct vis a vis B&N that is made possible by the fact that B&N would neither sign a non-disclosure agreement before discussing the patent matter, nor roll over for a couple of attempts by Microsoft to imply that there was such an agreement.

In the end, B&N signed an extremely narrow agreement that applied only to a set of charts meant to illustrate MS' case. That left B&N free to put MS' conduct in approaching B&N out in the open and make it part of the litigation. They do discuss the patents at issue, and of course argue that they are invalid for various familiar reasons (mainly prior art and obviousness) on the one hand, but it seems to me they are really going for the jugular by giving specific instances of MS having unclean hands in regard to specific patents as well, and specific actions and statements by MS and Nokia that indicate plans to combine their patent portfolios offensively in a way that violates antitrust laws.

All lawyer stuff, and I'm not one, but the thing is that by these means they build a case that is intended to support the quoted allegation, replying to a simple face-to-face fight over patents and licensing by trying to put MS on the defensive on multiple fronts, some of them perhaps criminal. Everything is arguable, and the judge will choose which parts end up in court, but B&N is not simply blowing hot air in their reply.

It's a hail mary manuever trying to, basicaly, flip the poker table over.
Since MS isn't doing anything that any other patent holder isn't doing, a B&N win on those terms would efectively end patent protection altogether. There are plenty of people that want exactly that but precious few courts willing to go along with it.
And invoking antitrust against MS to defend a Googgle product...?
Good luck with that, B&N.

And people are still wondering why we don't give a shit about the plight of these companies? Take all you want (ebooks, movies, music, games, food), give what you can, but not to any of the large conglomerates if you can avoid it.